Means for supporting and driving mixer drums



June 13, 1950 c. 1. BOHMER ET AL 1 MEANS FOR SUPPORTING AND DRIVING MIXER DRUMS Filed April 22, 1949 2 Sheets-Sheet 1 INVENTORS C/are/re 50/7/77Z/T BY Eugene Barker ATTORNEYS June 13, 1950 c. 1. BOHMER ET AL MEANS FOR SUPPORTING AND DRIVING MIXER DRUMS 'llllllllllll/IIIII/l/ Filed April 22, 1949 INVENTORS C/arence /50f1m@r Eugene Barker? ml A TTOP/VEYS Patented June 13, 1950 MEANS FOR SUPPORTING AND DRIVING MIXER DRUMS Clarence I. Bohmer and Eugene Barker, Columbus, Ohio, assignors to The Jaeger Machine Company, Columbus, Ohio, a corporation of Ohio Application April 22, 1949, Serial No. 89,042

3 Claims. 1

Our invention relates to means for supporting and driving a mixer drum. It relates, more particularly, to means for supporting and driving the mixer drum of a truck mixer, either of the horizontal drum type or of the inclined drum or high-dump type. The structure of our invention, however, is applicable to similar installations in connection with other types of equipment.

At the present time, mixer drums of truck mixers are usually supported for rotation by means of a trunnion and bearing disposed at the center of the drum at the forward end thereof and by rollers arranged to form a cradle at the rear end of the drum. This is true whether the drum is disposed for rotation about a horizontal axis or an inclined axis. The drum is usually driven by a ring gear or band extending around the drum which is engaged by a suitable pinion driven by means of the usual transmission, the ring gear and pinion being exposed.

It is the object of our invention to provide a supporting and driving structure for a mixer drum which is of such a nature that it is possible to have the driving gears completely en;- closed for protection and to have them running in oil for lubrication and smooth operation.

Another object of our invention is to provide driving means for a mixer drum which is of such a nature that the gears can be tightly meshed so as to eliminateback-lash and a great deal of noise, noise also being dampened by the presence of oil in the case enclosing the driving gears.

A further object of our invention is to provide a mixer drum supporting and driving structure which is of such a nature that the mixer drum may be aligned easily and quickly on the mixer frame relative to the supporting and driving means, thus eliminating considerable labor in adjusting and shimming the drum and supporting parts to obtain proper alignment.

A further object of our invention is to provide supporting and driving means of such a nature 'that the drum can be lifted out of the frame easily and quickly without dismantling the trunnion bearing.

Another object of our invention is to provide a structure of the type indicated which because it is self-contained and the gears thereof can be completely enclosed and protected eliminates the problems of maintaining proper alignment, of keeping dirt and foreign material out of the gears, and of excessive wear which would be caused by the dirt and foreign matter.

Another object of our invention is to provide a driving structure for the mixer of such a nature.

that since excessive back-lash can be eliminated, the pitch of the gears can be reduced materially as compared with open-type gearing, resulting in much smoother operation, particularly from the standpoint of impact on the gear teeth.

Another object of our invention is to provide a structure of the type indicated which is of such a nature that the parts thereof can be much smaller than the conventional open gear type of drive and, therefore, the structure can be fabricated at a much lower cost.

Various other objects will be apparent.

According to our invention, we provide a support for the mixer drum which includes the usual cradle structure for supporting the rear end of the drum. The forward end of the drum, however, is supported by a self-contained trunnion bearing and driving structure: This self-contained driving and supporting structure comprises a housing which contains the driving gears and which supports a rearwardly projecting output shaft or trunnion. The drum is supported on the trunnion by means of a spider which is keyed to the trunnion that is, in turn, driven by the gears disposed in the housing. The spider is provided with driving portions which engage with driving portions carried by a member secured to the forward end of the drum and carrying a drum-supporting sleeve. This sleeve cooperates with a bearing hub on the spider to support the drum on the trunnion shaft, flexible means bein disposed between the sleeve and bearing hub to permit initial proper alignment of the drum and to maintain such proper alignment.

The preferred embodiment of our invention is illustrated in the accompanying drawings wherein similar characters of reference designate corres onding parts and wherein:

Figure 1 is a side elevational view illustrating our invention applied to a mixing drum supported on an inclined axis.

Figure 2 is a vertical sectional view taken through the main part of our drum supporting and driving means.

Figure 3 is a transverse sectional view taken a ong line 3-3 of Figure 2.

Figure 4 is a detail in perspective of the driving connection between the spider and the bearin supporting member on the drum.

With reference to the drawings, we have illustrated in Figure 1 a supporting frame I which may be the frame of any suitable vehicle for carrying the mixing drum 2. For example, the frame I may be mounted on a truck chassis. In

this instance, the mixer drum 2 is on an inclined axis so that the truck mixer would be one of the high-dump type. The rear end of the inclined drum is supported by cradle rollers 3 which are carried by upstanding members 4 of the frame l,-the rollers .3 engaging a supporting band 5 carried bythe drum. The forward end of the drum 2 is carried and driven by our novel unit which we shall indicate generally by the numeral 6.

The engine 1 supported at the forward 'end .of the frame I will drive the conventional transmission 8 which is capable of forward-and reverse drive and which may be provided with an output shaft for driving a centrifugal pump B. The main output shaft of the transmission will serve to drive the unit through the medium of a universal drum ll connected to an enclosed gear reduction unit I2.

The unit I2 is in the form of a pedestal which supportswthe unit 6. Theunit l2 includes a housing [3 which enclosesagroup of gears 14 which are-in proper ratio and properly arranged to obtain the desired reduction. The finaldriven gear -I 5 of theunit l2 meshes with the large driven gear 16 of the unit 6 as shown best in Figure 2.

ittwill :benotedfrom'l igure 2 that the unit 6 includes a housing 11., in which the'main part of the gear i6 is disposed, this housing communicating at its lower side with the housing l3 and the gear l6 extending down into the housing [3. The housing I! is mounted in forwardly tilted position 'on the upper end of the housing l3 by means of-a-n intermediate housing portion 1 8 to-which-the lower end 'of housing I! is bolted and the upper-endof housing I3 is bolted. However, if the axis of .the drum 2 is horizontal, a different intermediate housing 'portion is 'substituted for the portion 18 to bring the housing portion I! into vertical position.

-The rgear lii is *keyed on a reduced portion I9 of a trunnion shaft 20. This shaft 20 is carried by the housing [1. For supporting the shaft on the housing 11, a roller bearing 2| is secured to the forward wall of the housing and a roller bearing 22 is secured to the rear wall-of the housing. The inner race of the bearing 22 engages the hub -23.of the gear l6 at the "rear side thereof while the forward side'of the hub isengaged by a thrust collar or spacer 24 which is engaged by the inner race of the bearing :2 Thus, the shaft 28 is rotatably carried by the housing H.

The shaft2ll extends rearwardly through the rear wall-of the housing H. The projecting portion of this trunnion shaft, which is the output shaft of the unit 6, carries a drum edriving member .in the form of a spider '25 which is illustrated best in Figures 3 and 4. The spider 25 is provided with ahub 28 into which the reduced rear end 21 of shaft 2-0 projects and which is keyed to the shaft by means -of a'lrey 28. The rear extremity of-the shaft -2-il-is threaded to receive a nut 29 which fits into a recess :3?! at the rear side of the hub. This nut engages the shoulder 3! on the hub and keeps the spider hub 2b in contact with a spacer sleeve 32 disposed between the hub and a shoulder 33 at the forward end of shaft section 21. lhus, the spider 25 will be maintained in a position spaced behind the housing I! on theshaft 20.

'The spider 25 .is provided with four driving notches 34 formed in its edge at 90 intervals. Each of these driving notches 34 is adapted to engage a forwardly projecting .lug '35 carried .by a bearing support 36 which is welded or otherwise secured to the forward end of the drum 2. The notches 34 receive the driving lugs 35 when the drum 2 is positioned on the frame and bolts and collar units 31 prevent pullingof the lugs 35 forwardly from the notches 34. It will be apparent that although we have indicated that four sets of notches 34 and lugs 35 are provided, it is to be understood that any desired number of "such units may be provided.

"39 that has its larger end forwardly.

the sleeveclosely surrounds the hub 26 of member 25. The sleeve 38 is provided with a reduced forward edge 42 which fits within a circular flange 43 projecting'rearwardly from the spider.

The rubber sleeve 40 will absorb or compensate for any misalignment between the mixer drum 2 and the trunnion shaft 20, it being understood that sufficient play is providedbetween the spider-notches 34 and the lugs 35 to permit relative movement between members 25 and 36 due to misalignment.

'Withxthis structure, the housing l3 and I! will completely enclose the driving gears and these housings may be filled with oil-so as to obtain proper lubrication of the gears .and reduce noise. The gear 16 and -the gear 15 as well as the other gears in the .housingl3 will be completely en-. closed and protected from dirt and foreign mat-. ter. Furthermore, because they will operate in a bath of oil, noise and wear will .be reduced considerably. Back-lash between the gears can be eliminated-since the gears can be tightly meshed and the pitch of the gears can be reduced materially as compared with open-type gearing. Furthermore, these gears will be relatively small and lower in cost.

since the unit .6 is self-contained, the drum 2 can be aligned much more easily-on the frame. In mounting the drum :on the frame, after the unit 6 is properly positioned, it is merely necessary to support the drum 2 .on the cradle rollers and .then slide it forwardly .until the lugs 35 slip into the notches 34 and the sleeve 38 slides over the hub 26 which will be supporting the rubber sleeve 40. Then the bolt units 31 are mounted on the lugs 35 to .prevent accidental removal of the lugs from the notches. Because of the provision 'of the rubber sleeve 40. and the notches 34 and lugs 35, misalignment of the drum on the frame will merel produce slight relative movement between the .members35and 25. The drum can beeasily removed, if necessary, merely by removing bolts 31 and moving the drum rearwardly toslide the lugs 35 from .the notches 34, the spider 25staying in positionon .the shaft 20. Thus, in removing the .drum, it is not necessary to dismantle the trunnion bearing as with prior art structures. The drum can be aligned initially relative to the unit 6 without using shims, and alignment will be substantially maintained, the rubber sleeve 40, however, permitting any slight misalignment which .might becaused during operation of the truck by flexing of the frame.

The trunnion shaft .20 .is preferably hollow so that a water passageway 44 extends completely therethrough. The forward end of this passageway, as shown inF-igure 1, is connected by a suitable swivel coupling 45 to a water pipe 46 leading from the pump 9. The rear threaded end of the shaft 20 has a pipe 46a threaded thereon which carries the water distributing bell 41 disposed within the mixer.

As previously indicated, the driving and supporting unit of our invention can be used either with a horizontally disposed drum or an inclined drum. When the drum is horizontally disposed, as previously indicated, the housing I! will be vertical. Therefore, the driven gear IE will be vertical and a beveled gear need not be used as in the structure shown in Figure 2.

It will be apparent from the above description that we have provided a novel mixer drum supporting and driving mechanism. A number of advantages of this structure have been discussed and others will be apparent.

Having thus described our invention, what we claim is:

1. Apparatus for supporting and driving a rotatable mixer drum or the like comprising a supporting frame, rollers on said frame for providing a cradle for supporting one end of the drum and means on the frame for supporting the other end of the drum, said means comprising a trunnion shaft supported on said frame and projecting towards the end of the drum, means for driving said shaft, a driving spider having a hub keyed on said shaft, said spider being provided with a plurality of driving notches in its periphery, a bearing support carried by the adjacent end of the drum and disposed adjacent the spider at the inner side thereof, said support having a sleeve surrounding the hub of said spider and having a plurality of lugs spaced outwardly from its axis which extend in an axial direction into said notches of the spider, removably retaining members carried by the lugs for normally preventing axial displacement of said lugs from said notches, the sleeve of the bearing member having a socket of larger diameter than the hub of the spider which it receives, the socket being tapered with its smaller end away from the spider member, a tapered rubber sleeve disposed in said socket, sufficient play being provided between said lugs and notches to permit said rubber sleeve to compensate for axial misalignment between the mixer drum and the trunnion shaft, and a circular flange carried by the inner side of said spider for receiving the outer end of said sleeve of the bearing member.

2. Apparatus for supporting and driving a rotatable mixer drum or the like comprising a supporting frame, rollers on said frame for providing a cradle for supporting one end of the drum and means on the frame for supporting the other end of the drum, asid means comprising a, trunnion shaft supported on said frame and projecting towards the end of the drum, means for driving said shaft, a driving spider having a hub keyed on said shaft, said spider being provided with a plurality of driving notches in its periphcry, a bearing support carried by the adjacent end of the drum and disposed adjacent the spider at the inner side thereof, said support having a sleeve surrounding the hub of said spider and having a plurality of lugs spaced outwardly from its axis which extend in an axial direction into said notches of the spider, the sleeve of the bearing member having a socket of larger diameter than the hub of the spider which it receives, and a, rubber sleeve disposed in said socket, sufficient play being provided between said lugs and notches to permit said rubber sleeve to compensate for axial misalignment between the mixer drum and the trunnion shaft.

3. Apparatus for supporting and driving a rotatable mixer drum or the like comprising a supporting frame, means on said frame for supporting one end of the mixer driun to permit slight lateral movement of the axis of the drum, means on the frame for supporting the other end of the drum, said means comprising a trunnion shaft supported on said frame and projecting towards the end of the drum, means for driving said shaft, a driving member keyed on said shaft and a driven member carried by the adjacent end of the drum and disposed adjacent the driving member, said driving member and said driven member having interfitting driving portions, said driven member having a sleeve which surrounds a hub on said driving member, said sleeve having a socket of larger diameter than said hub, and a compressible sleeve disposed in said socket, sufiicient play being provided between the interfitting portions of said driving and driven member to permit said compressible sleeve to compensate for axial misalignment between the mixer drum and the trunnion shaft.

CLARENCE I. BOHMER. EUGENE BARKER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 678,399 Hays July 16, 1901 856,384 Armbruster June 11, 1907 934,834 Pointon et al Sept. 21, 1909 971,387 Lips Sept. 27, 1910 2,295,282 Mall Sept. 8, 1942 2,328,830 Maxon Sept. 7, 1943 2,460,628 Fawick Feb. 1, 1949 FOREIGN PATENTS Number Country Date 41,150 Denmark Sept. 24, 1929 

